Timeline: When the Titanic sub vanished, the race to find it and its eventual demise

The five people aboard a submersible visiting the wreck of the Titanic died after a catastrophic loss of the pressure chamber, US Coast Guard officials said on Thursday (June 22).  A "debris field" matching the submersible was discovered by a robotic deep-sea vessel.

Here is a timeline of events since the start of the trip, organised by OceanGate Expeditions, to visit the wreckage:

FRIDAY

Expedition sets off from St. John's, Newfoundland, Canada.

SATURDAY

Saturday (Jun 17) evening - British billionaire and adventurer Hamish Harding, one of those aboard the submersible, posts on Facebook: "Due to the worst winter in Newfoundland in 40 years, this mission is likely to be the first and only manned mission to the Titanic in 2023. A weather window has just opened up and we are going to attempt a dive tomorrow."

"More expedition updates to follow IF the weather holds!"

He does not post again on Facebook.

SUNDAY

8am GMT (4pm, Singapore time) - Time the submersible originally aimed to start its descent, according to a post by Harding on Instagram. But it starts its descent later, according to the US Coast Guard.

12pm GMT (8pm, Singapore time) - Titan submersible starts what should be a two-hour descent to the Titanic wreck, which lies at a depth of 12,500m in the North Atlantic, US Coast Guard says.

1.45pm GMT (9.45pm, Singapore time) - Communications between the submersible and the surface vessel are lost 1 hour and 45 minutes after starting its descent, the US Coast Guard says.

7pm GMT (3am, Singapore time) - The submersible is scheduled to return to the surface, the US Coast Guard says. It fails to appear.

9.40pm GMT (5.40am, Singapore time) - Coast Guard receives report about an overdue submersible from the Canadian Research Vessel Polar Prince with five people aboard diving to view the Titanic wreck about 900 nautical miles east of Cape Cod on the US coast.

MONDAY

US and Canadian ships and planes are swarming the area, some dropping sonar buoys that can monitor to a depth of 3,962m, US Coast Guard Rear Admiral John Mauger says. He adds it is a remote area and a challenge to conduct a search. Officials have also asked commercial vessels for help.

TUESDAY

MORNING - The family of Pakistani-born businessman Shahzada Dawood confirm he is aboard with his 19-year-old son Suleman. They ask for prayers for their safety.

2.50pm GMT (10.50pm, Singapore time) - France says it will help with search by deploying Atalante, a ship equipped with a deep-sea diving vessel and managed by the Ifremer ocean research institute.

DURING THE DAY - Sounds detected over several hours by Canadian Lockheed P-3 Orion aircraft, equipped with gear to trace submarines. The US Coast Guard - which announces this on Wednesday - does not give a precise timing.

CNN and Rolling Stone magazine reports Canadian aircraft detected banging sounds at 30-minute intervals. Rolling Stone says sonar picks up more banging four hours later. CNN also reports later sounds but does not describe them as banging.

Harding's friend, Jannicke Mikkelsen, says: "And as it stands right now, it would be a miracle if they are recovered alive."

WEDNESDAY

DURING THE DAY - US Coast Guard, US Navy, Canadian Coast Guard and OceanGate Expeditions establish a unified command to handle the search.

6am GMT (2pm, Singapore time) - US Coast Guard announces Canadian P-3 aircraft detected underwater noises. It says remotely operated vehicle (ROV) searches are directed to the area of the sounds and the data are also sent to US Navy experts for analysis.

LATE ON WEDNESDAY - French research ship, equipped with a deep-sea diving vessel, expected to arrive at search area.

THURSDAY

10am GMT (6pm, Singapore time) - Rough deadline for when the air in the submersible will run out, based on the US Coast Guard's estimate. The vessel has 96 hours of air supply from the time it is sealed, according to its specifications. This depends on the vessel being intact and other factors, such as whether the sub still has power in the icy depths.

6pm GMT (2am, Singapore time) - A debris field that was found near the wreckage of the Titanic in the North Atlantic contains the pieces of the Titan submersible, officials said.

7pm GMT (3am, Singapore time) - The debris was consistent with a catastrophic loss of the pressure chamber and an implosion, the US Coast Guard said. There were no survivors.